Antioxidant and renal protective effects of house cricket (Acheta domesticus) powder in a streptozotocin-induced diabetic nephropathy model

House cricket powder (HCP) is an emerging functional food ingredient rich in bioactive metabolites. We evaluated its antioxidant capacity and ability to ameliorate renal dysfunction in streptozotocin‐induced diabetic nephropathy. Specific-pathogen-free male ICR and C57BL/6J mice (6–8 weeks, 25–30 g) were randomised (block size = 4) and treated by oral gavage with HCP (300, 1 000, 3 000 mg kg⁻¹) or vehicle for 14 (or 60) days. A positive control group received astaxanthin (10 mg kg⁻¹). Total antioxidant capacity (TAC), superoxide dismutase (SOD) activity, and gene expression of Nrf2, HO-1, SOD2, CAT, and NF-κB were quantified in liver and kidney by colorimetric assays, RT-qPCR, and Western blotting. Renal function was assessed by plasma blood urea nitrogen (BUN), creatinine (CRE), and histopathology. All procedures were approved by the Institutional Animal Care and Use Committee of Nagahama Institute of Bio-Science and Technology (approval #099). HCP produced a dose-dependent increase in renal TAC (+40 % at 1 000 mg kg⁻¹; P < 0.01) and SOD (+20 % at 1 000 mg kg⁻¹; P < 0.05). HCP (3 000 mg kg⁻¹, 60 d) down-regulated diabetic elevations in BUN (–28 %) and CRE (–24 %), and reduced the proportion of degenerated glomeruli from 46 % to 19 % ( P < 0.01). Molecular analysis revealed significant up-regulation of Nrf2 (1.8-fold) and HO-1 (2.1-fold) transcripts, with concomitant suppression of NF-κB protein. HCP activates the Nrf2 antioxidant pathway and preserves renal structure and function under diabetic oxidative stress. These findings support HCP as a sustainable dietary intervention for the prevention of diabetic nephropathy.